Background— Circulating very-long-chain saturated fatty acids (VLCSFAs) may play an active role in the origin of cardiometabolic diseases.

Methods and Results— We measured 3 VLCSFAs (C20:0, C22:0, and C24:0) in plasma and erythrocytes using gas-liquid chromatography among 794 incident coronary heart disease (CHD) cases who were prospectively identified and confirmed among women in the Nurses’ Health Study (NHS; 1990–2006) and among men in the Health Professionals Follow-Up Study (HPFS; 1994–2008). A total of 1233 CHD-free controls were randomly selected and matched to cases in these 2 cohorts. Conditional logistic regression was used to estimate hazard ratios and 95% confidence intervals. Plasma VLCSFAs were correlated with favorable profiles of blood lipids, C-reactive protein, and adiponectin in the NHS and HPFS and with fasting insulin and C-peptide levels in a nationally representative US comparison population. After multivariate adjustment for lifestyle factors, body mass index, diet, and long-chain n-3 and trans fatty acids, total VLCSFAs in plasma were associated with a 52% decreased risk of CHD (pooled hazard ratio, 0.48; 95% confidence interval, 0.32–0.72, comparing extreme quintiles; Ptrend<0.0001). For VLCSFAs in erythrocytes, a nonsignificant inverse trend with CHD risk was observed (pooled hazard ratio, 0.66; 95% confidence interval, 0.41–1.06, comparing extreme quintiles; Ptrend=0.16).

Conclusions— In US men and women, plasma VLCSFAs were independently associated with favorable profiles of blood lipids and other cardiovascular disease risk markers and a lower risk of CHD. Erythrocyte VLCSFAs were associated with nonsignificant trends of lower CHD risk. Future studies are warranted to elucidate the underlying biological mechanisms.